Spark plug tool



FIG. 1 is a top, front and right side perspective view of a spark plug tool showing my new design;

FIG. 2 is a rear elevation view thereof;

FIG. 3 is a left side elevation view thereof, the top, bottom, and right side elevation views being identical; and,

FIG. 4 is a cross sectional view taken along the lines 4--4 of FIG. 2. 

The ornamental design for a spark plug tool, as shown and described. 